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应用神经网络的复杂物体三维测量

光学学报 2007年第8期27卷 1435-1439页

作者：唐燕陈文静四川大学光电子科学技术系成都610064

将神经网络引入基于结构光投影的复杂物体三维面形测量。在测量过程中,利用神经网络强大的函数逼近能力,得到离散条纹图的连续逼近函数,从中解出物体的相位分布信息,获得物体的三维面形分布。应用神经网络方法,在结构光投影条件下,只需... 详细信息

将神经网络引入基于结构光投影的复杂物体三维面形测量。在测量过程中,利用神经网络强大的函数逼近能力,得到离散条纹图的连续逼近函数,从中解出物体的相位分布信息,获得物体的三维面形分布。应用神经网络方法,在结构光投影条件下,只需要获取一幅条纹图,便可以完成复杂物体的三维面形测量。该方法相比传统的傅里叶变换轮廓术,不存在滤波操作,不会在测量过程中丢失被测物体的高频分量,具有更高的空间带宽积和灵敏度,能准确测量出复杂物体的细节,更加适用于恢复复杂物体的三维面形。并且该方法在条纹图存在阴影的情况下与傅里叶变换轮廓术相比,能更好地提取出物体的相位信息,恢复物体的三维面形。模拟及实验均验证了该方法的可行性。

关键词：三维面形测量神经网络函数逼近傅里叶变换轮廓术

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盾构隧道纵向地震响应分析

西南交通大学学报 2007年第3期42卷 283-287页

作者：耿萍何川晏启祥西南交通大学土木工程学院四川成都610031

为了探讨盾构隧道的纵向地震响应特性,采用地层-隧道整体三维有限元模型,对武汉长江越江盾构隧道的地震响应进行了分析,主要研究了合理的盾构隧道力学模型、隧道与地层之间的相互作用以及隧道的振动特性.通过隧道与地层的整体分析,得到... 详细信息

为了探讨盾构隧道的纵向地震响应特性,采用地层-隧道整体三维有限元模型,对武汉长江越江盾构隧道的地震响应进行了分析,主要研究了合理的盾构隧道力学模型、隧道与地层之间的相互作用以及隧道的振动特性.通过隧道与地层的整体分析,得到了盾构隧道位移和应力的分布及其随时间的变化曲线.计算结果表明:压缩波引起的纵向拉、压应力和剪切波引起的扭曲变形是隧道抗震设计的关键.

关键词：盾构隧道三维有限元法地震响应分析

Microstructure Evolution and Deformation Behavior of Metastable β-Titanium Alloy Ti55511 in Die Forging

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稀有金属材料与工程 2024年第9期53卷 2420-2429页

作者： Gu Bin Xiong Zhihao yang ping Gu Xinfu yan Mengqi Sha Aixue School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China AECC Beijing Institute of Aeronautical Materials Beijing 100095China

The effect of die forging on the microstructure evolution and deformation behavior of metastable β-titanium alloy Ti55511 was investigated by electron backscatter *** die forging,the alloy Ti55511 was subjected to multi-pass forging to optimize the microstructural heterogeneity(texture)which can cause mechanical behavior anisotropy of titanium *** show that after die forging,Ti55511 components exhibit different microstructures and textures in different local ***fiber texture is found in all areas with different degrees of *** recrystallization occurs in the area where large strain occurs during the early stage of die ***-weave microstructure forms in most local areas.

关键词： metastableβ-titanium alloy microstructure texture die forging EBSD

Effects of lifestyle interventions on rural patients with type 2 diabetes mellitus

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World Journal of Diabetes 2020年第6期11卷 261-268页

作者： Bo Wang Xiao-Li Mu Juan Zhao Hai-ping Jiang Shan-Shan Li Ge yan Ying-Ying Hua Xue-Yi Ren Li-Xia Xing yan Liang Shu-Dong Zhang Yu-Chi Zhao Department of Internal Medicine Yantaishan HospitalYantai 264025Shandong ProvinceChina Department of Osteoarthropathy Yantaishan HospitalYantai 264025Shandong ProvinceChina

BACKGROUND The prevalence of type 2 diabetes mellitus(T2DM)is rising rapidly in rural areas,and lifestyle interventions can effectively reduce the blood glucose levels of patients with ***,current dietary and exercise guidelines are still at experimental stages and are difficult for subjects to understand and *** Human Metabolism Analyzer provides real life interventions for the prevention and treatment of T2DM,and our pilot research has demonstrated its effectiveness and good *** To investigate the effect of and compliance with lifestyle interventions in rural patients with *** A total of ten rural villages were randomly selected in Chaoshui Township,Penglai City,Shandong Province,China,to conduct health screening among residents aged 50 years or *** rural village represented a group,and 12 patients with T2DM were randomly selected from each group(total:120)to participate in this study and receive real life lifestyle interventions and medication *** interventions included changing the meal order(A),postprandial activities(B),resistance exercise(C),and reverse abdominal breathing(D).Diabetes education was conducted at least once a month with a weekly phone follow-up to monitor exercise and *** circumference,blood pressure,body mass index(BMI),motor function,body composition,fasting blood glucose,and glycated hemoglobin(HbA1c)were analyzed before and 3 mo after the ***,patient compliance and adjustments of hypoglycemic drugs were *** A total of 109 subjects completed the *** compliance rates for lifestyle interventions A,B,C,and D were 57.79%,60.55%,64.22%,and 75.23%,*** the subjects who received hypoglycemic drugs,the dose was reduced 2 to 3 times based on blood glucose in 54(67.50%)subjects and was tapered and discontinued in 5(6.25%)subjects within 3 mo,with no significant fluctuations in blood glucose after dose reduction and *** l

关键词： Type 2 diabetes mellitus Lifestyle interventions Body mass index

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金融行业异质型人力资本识别与管理

南方金融 2010年第3期 30-34,73页

作者：鄢平广东科学技术职业学院经济管理学院广东广州510640

文章分析了金融业异质型人力资本的普遍特征如模糊集、存量不断发展变化,并阐述了其行业特征如高端性、高实践成本和维护成本,在此基础上提出了金融业异质型人力资本识别方法和管理建议。

关键词：异质型人力资本积累识别模型

高频高压交流电源应用于介质阻挡放电特性的研究

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高电压技术 2006年第3期32卷 78-80页

作者：邵建设严萍中国科学院电工研究所

应用电压幅值和频率都可调的高频高压交流电源研究了大气压空气中同轴介质阻挡放电的特性;介绍了该介质阻挡放电装置的工作原理后研究了电源逆变器交流侧电路工作于固有谐振频率和1/3固有谐振频率下负载电压及其频率、放电电流、谐振电... 详细信息

应用电压幅值和频率都可调的高频高压交流电源研究了大气压空气中同轴介质阻挡放电的特性;介绍了该介质阻挡放电装置的工作原理后研究了电源逆变器交流侧电路工作于固有谐振频率和1/3固有谐振频率下负载电压及其频率、放电电流、谐振电流随着逆变器直流侧电压变化的规律,比较了在逆变器直流侧电压相同下的负载电压和放电电流的特点。研究结果表明,在初始放电发生前,电源的逆变电路直流侧电压线性增加,负载电压和放电电流随之增加,负载性质始终为容性;放电发生后,负载电压近似恒定,放电电流近似线性增长,负载性质为阻容性;在外加电源电压的正、负半周内,微放电电流波形不对称,分别呈“似辉光放电”和“丝状放电”的特点。

关键词：高频高压大气压空气同轴介质阻挡放电微放电似辉光放电丝状放电

Nomogram for predicting pathological complete response and tumor downstaging in patients with locally advanced rectal cancer on the basis of a randomized clinical trial

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Gastroenterology Report 2020年第3期8卷 234-241,I0002页

作者： Jian-Wei Zhang Yue Cai Xiao-Yu Xie Hua-Bin Hu Jia-Yu Ling Ze-Hua Wu ping Lan Xiao-Jian Wu Mei-Jin Huang Hui Wang Liang Kang Zhi-yang Zhou Jian-ping Wang yan-Hong Deng Department of Medical Oncology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases GuangzhouGuangdongP.R.China Department of Colorectal Surgery The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Radiology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background:Preoperative fluoropyrimidine with radiotherapy was regarded as the standard of care for locally advanced rectal cancer(LARC).The model for predicting pCR in LARC patients was based on standard treatment *** study aimed to establish a nomogramwith pretherapeutic parameters and different neoadjuvant regimens for predicting pathologic complete response(pCR)and tumor downstaging or good response(ypT0-2N0M0)after receiving neoadjuvant treatment in patients with LARC based on a randomized clinical ***:Between January 2011 and February 2015,309 patients with rectal cancer were enrolled from a prospective randomized study(NCT01211210).All pretreatment clinical parameters were collected to build a nomogram for predicting pCR and tumor *** model was subjected to bootstrap internal *** predictive performance of the model was assessed with concordance index(C-index)and calibration ***:Of the 309 patients,53(17.2%)achieved pCR and 132(42.7%)patients were classified as tumor downstaging with *** on the logistic-regression analysis and clinical consideration,tumor length(P=0.005),tumor circumferential extent(P=0.036),distance from the anal verge(P=0.019),and neoadjuvant treatment regimen(P<0.001)showed independent association with pCR following neoadjuvant *** tumor length(P=0.015),tumor circumferential extent(P=0.001),distance from the anal verge(P=0.032),clinical T category(P=0.012),and neoadjuvant treatment regimen(P=0.001)were significantly associated with good tumor downstaging(ypT0-2N0M0).Nomograms were developed to predict the probability of pCR and tumor downstaging with a C-index of 0.802(95%confidential interval[CI],0.736-0.867)and 0.730(95%CI,0.672-0.784).Internal validation revealed good performance of the calibration ***:The nomogramprovided individual prediction responses to different preoperative treatment for patients with rectal *** model might help physicians

关键词： nomogram pathological complete response tumor downstaging locally advanced rectal cancer

Hydrodynamic characteristics of a typical karst spring system based on time series analysis in northern China

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China Geology 2021年第3期4卷 433-445页

作者： Yi Guo Feng Wang Da-jun Qin Zhan-feng Zhao Fu-ping Gan Bai-kun yan Juan Bai Haji Muhammed China Aero Geophysical Survey and Remote Sensing Center for Natural Resources China Geological SurveyBeijing 100083China Chinese Academy of Environmental Planning Beijing 100012China Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Applied Natural Science Adama Science and Technology UniversityP.O.Box 1888AdamaEthiopia

In order to study the hydrodynamic characteristics of the karst aquifers in northern China,time series analyses(correlation and spectral analysis in addition with hydrograph recession analysis)are applied on Baotu Spring and Heihu Spring in Jinan karst spring system,a typical karst spring system in northern *** show that the auto-correlation coefficient of spring water level reaches the value of 0.2 after 123 days and 117 days for Baotu Spring and Heihu Spring,*** regulation time obtained from the simple spectral density function in the same period is 187 days and 175 days for Baotu Spring and Heihu *** auto-correlation coefficient of spring water level reaches the value of 0.2 in 34-82 days,and regulation time ranges among 40-59 days for every single hydrological *** delay time between precipitation and spring water level obtained from cross correlation function is around 56 days for the period of 2012-2019,and varies among 30-79 days for every single hydrological *** addition,the spectral bands in cross amplitude functions and gain functions are small with 0.02,and the values in the coherence functions are *** these behaviors illustrate that Jinan karst spring system has a strong memory effect,large storage capacity,noticeable regulation effect,and time series analysis is a useful tool for studying the hydrodynamic characteristics of karst spring system in northern China.

关键词： Karst spring Karst aquifer Hydrodynamic Time series analysis Correlation analysis Spectral analysis Hydrogeological survey engineering Jinan Shandong Province China

Inhibition of platelet aggregation by polyaspartoyl L-arginine and its mechanism

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Acta Pharmacologica Sinica 2004年第4期25卷 71-75页

作者： Yin-ye WANG, Zhi-yu tang, Min DONG, Xiao-yan LIU, Shi-qi PENG2 Department of Pharmacology, Department of Medicinal Chemistry, 2 Schoolof Pharmaceutical Sciences, Peking University, Beijing 100083, China Department of Pharmacology Department of Medicinal Chemistry School of Pharmaceutical Sciences Peking University

AIM: To observe the oral anti-platelet efficacy and the potential action mechanism of polyaspartoyl L-arginine (PDR), a new L-arginine rich compound. METHODS: Platelet aggregation was conducted by Born’s method; bleeding time was determined using tail’s bleeding time in mice; platelet adhesion was carried out with glass bottle method; nitric oxide (NO) was tested with Griess’ method; and cAMP, thromboxane B2 (TXB2) and 6-keto-PGF1α were assessed with commercial kits. RESULTS: The inhibition by PDR (15-60 mg/kg ig or 10 mg/kg iv) of platelet aggregation induced by adenosine diphosphate (ADP), collagen or thrombin at 1 h after oral administration or at 20 min after iv injection for rats (P<0.01), and its (15 mg/kg, ig) inhibition of ADP-induced platelet aggregation for rabbits during 6 h after administration were observed. PDR (15-60 mg/kg) prolonged the bleeding time of mice (P<0.05) and (30 mg/kg) increased NO concentration in plasma. On the other hand PDR did not change the contents of cAMP in platelet and TXB2 or 6-keto-PGF1α in plasma. CONCLUSION: PDR is a novel, oral effective platelet aggregation inhibitor and its action mechanism possibly related to increasing NO generation.

关键词： platelet aggregation bleeding time platelet adhesiveness polyaspartoyl L-arginine nitric oxide cyclic AMP Thromboxane B2 6-ketoprostaglandin F1 alpha